Vacuum Cleaner

ABSTRACT

A vacuum cleaner includes a body having a cavity, an outlet for cleaned air, a filter removably mounted in the cavity upstream of the outlet, at least one device mounted in the body upstream of the filter for separating and collecting dirt and dust entrained in an induced airflow through the cleaner, and a closure for closing an opening in the cavity, the closure being openable for providing access to the filter and separation device through the opening. An arm extends into the cavity for engaging a formation on the filter, the latter holding the arm in a retracted position. If the filter or a component of the separation device is omitted or incorrectly inserted in the body, the arm adopts an extended position and prevents the closure from being closed. In this manner the user is immediately alerted to the fact that the filter or a component of the separation device is not correctly in-situ and remedial action can be taken.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a vacuum cleaner and more particularly to a vacuum cleaner incorporating an arrangement for preventing operation of the cleaner if at least a filter within the cleaner is absent.

2. Related Background Art

Hitherto, disposable permeable dust bags have been widely used in vacuum cleaners to separate dirt and dust from the airflow and to contain the separated matter for subsequent disposal. It will be appreciated that the operation of a vacuum cleaner without a bag installed is clearly undesirable, since the collected dirt and dust will either pass straight through the cleaner or will block any subsequent filters or contaminate the motor.

In order to overcome this problem, vacuum cleaners have been proposed which comprise arrangements for alerting users to the absence of a dust bag. One such vacuum cleaner is disclosed in U.S. Pat. No. 5,940,931 and comprises a mechanical arrangement that prevents the bag chamber cover from being closed when the dust bag is absent. Another such vacuum cleaner is disclosed in EP0934721 and comprises an electrical sensor which prevents the vacuum cleaner from being energised when the dust bag is absent.

It is now commonplace for vacuum cleaners to comprise a cyclonic separation unit instead of a dust bag. One such vacuum cleaner is disclosed in GB2377622 and comprises a cylindrical cyclonic main separation unit and a downstream filter mounted axially thereof at one end of the vacuum cleaner body, the filter acting to catch any dust which is carried over from the main separation unit to prevent dust contamination of the motor and the surroundings. A visual indicator in the form of a flag projects from an external surface of the vacuum cleaner body to alert users to the absence of the filter and also to prevent connection of the motor and fan unit to the air outlet from the body when the filter is absent. In this manner reassembly of the cleaner without the filter can be avoided.

Although modern cyclonic separators are effective in removing fine particles from the vacuum cleaner airflow, it is desirable to provide a further stage of separation between the cyclone outlet and the fan. This is normally a large porous filter of the HEPA type, which must be cleaned or renewed periodically. Typically, such filters are located in a chamber having a closure, which can be opened to provide easy access to the filter, unlike the arrangement of GB2377622 where the filter is enclosed within vacuum cleaner body and hidden from view.

Generally simple cyclonic separation units comprise a single cyclone having an outlet duct or so-called vortex finder, located axially in a cyclone chamber. In some cases, the vortex finder is constructed as a perforated tube, which is susceptible to blocking by coarse and fibrous dirt particles in use, and can require occasional cleaning.

High separation efficiency has been achieved in modem cyclonic vacuum cleaners with a second stage of separation mounted downstream of a low efficiency cyclonic separation unit, the second stage comprising an array of parallel-connected cyclones of small diameter. In use, such small diameter cyclones can become blocked and accordingly require occasional cleaning.

It will be appreciated from the foregoing that some degree of dismantling of such high efficiency vacuum cleaners is occasionally necessary for cleaning the or each separation devices therein. However a problem with this is that users can reassemble the devices incorrectly or omit one or more device component altogether with the result that dirt and dust could either pass straight through the cleaner or block any subsequent filter or contaminate the motor.

We have now devised a vacuum cleaner which alleviates the above-mentioned problem.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a vacuum cleaner having a body portion comprising:

a cavity; an outlet for cleaned air; a filter removably mounted in the cavity upstream of the outlet; at least one device mounted upstream of the filter for separating and collecting dirt and dust entrained in an induced airflow through the cleaner; a closure for closing an opening in the cavity, the closure being openable for providing access to the filter through said opening; and displaceable means extending into the cavity and arranged to engage the filter for location of the displaceable means in a first position when the filter is correctly in-situ and for location of the displaceable means in a second position when the filter is not correctly in-situ, said displaceable means comprising a portion which obstructs the closure to prevent the closing thereof when the displaceable means is in said second position.

In use, the closure can be opened to conveniently gain access to the filter, so that the latter can be inspected, cleaned or replaced. When correctly in-situ, the filter is engaged by the displaceable means, such that the latter is held in its first position and operation of the closure is uninhibited. However, if the filter is not correctly in-situ, for example when it is absent from the cavity or incorrectly fitted, the displaceable means is positioned in its second position, such that the closure cannot be closed. In this manner the user is immediately alerted to the fact that the filter is not correctly in-situ and remedial action can be taken.

Preferably, at least a portion of the or each separation device in the body is removable through said opening upon removal of the filter.

Preferably, said filter is mounted on or against a portion of a said separation device, such that the latter positions the filter correctly in-situ. In this manner, omission or incorrect installation of the portion of the device will also cause the filter to be positioned out-of-situ. Hence closing of the closure is prevented and the user is again alerted that a component of the cleaner is missing or that one or more components are incorrectly positioned.

Preferably, said portion of said separation device is mounted on or against a further portion of said separation device. In this manner, omission or incorrect installation of the further portion will cause the first-mentioned portion and hence the filter to be positioned out-of-situ.

Preferably, said separation device is mounted on or against a portion of a further separation device. In this manner, omission or incorrect installation of the further separation device will cause the first-mentioned device and hence the filter to be positioned out-of-situ.

Preferably the displaceable means is arranged to engage a formation on the filter, the formation being arranged such that the displaceable means is only held in said first position when the filter is correctly in-situ in the cavity.

Preferably the displaceable means is biased into said second position.

Preferably the displaceable means comprises an arm having a first end arranged to engage the filter and a second end arranged to obstruct the closure when the filter is not correctly in-situ.

Preferably the arm is pivotally mounted intermediate its opposite ends.

Preferably the body is tubular, the cavity being disposed at one end of the body and said closure being provided across an opening in said end, wherein the or each separation device is stacked longitudinally inside the body between said cavity and the opposite end of the body.

Preferably a said separation device is a dust bag or a cyclone separator. In the latter case, the cyclone separator may comprise a plurality of cyclones.

Preferably the filter is biased out of situ so that the filter is only held correctly in-situ if all of the required components of the cleaner are present and correctly fitted.

Preferably the body is arranged to be substantially upright when in use, such that the filter is biased by gravity.

Preferably said body portion is detachably mounted to a chassis of the cleaner, so that the body can be removed from the chassis for emptying the separating device and for cleaning of the components within the body.

Preferably said chassis is adapted to prevent attachment of the body thereto when said closure is open, so as to alert the user that the filter is not correctly in-situ and that remedial action should be taken.

Preferably said chassis defines a socket into which the body only fits when said closure is closed.

Embodiments of the present invention will now be described by way of examples only and with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view through a portion of an embodiment of vacuum cleaner in accordance with the present invention, when all components of the vacuum cleaner are correctly in-situ;

FIG. 2 is a perspective view of a filter of the vacuum cleaner of FIG. 1;

FIG. 3 is an isometric sectional view of the vacuum cleaner portion of FIG. 1, when a component of the vacuum cleaner is absent;

FIG. 4 is schematic sectional view through a portion of a second embodiment of vacuum cleaner in accordance with the present invention; and

FIG. 5 is schematic side view of third embodiment of vacuum cleaner in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1 of the drawings, there is shown a portion of an upright vacuum cleaner comprising a tubular main body 10 having an open upper end. A closure 11 for closing the upper end of the main body 10 is hinged at point 12 to the upper end of a tubular side wall 17 of the main body 10. The closure 11 is provided with a catch 13 for engaging the main body, in order to maintain the closure 11 in its closed position.

The lower end of the main body 10 houses a cyclone separator 14, which comprises a cyclone chamber 15 bounded by a tubular sidewall 16. The upper end of the tubular sidewall 16 is connected to the external tubular sidewall 17 of the main body 10 by a radially-extending wall 18, which lies normal to the axis of the main body 10 and which defines a shelf or ledge.

A vortex finder portion 19 of the cyclone separator 14 comprises a tubular portion 20, which depends axially into the upper end of the cyclone chamber 15 and comprises a perforated lower end 21, through which cleaned air leaves the cyclone chamber 15 and flows upwardly. The upper end of the vortex finder 19 comprises a radial flange 22 which seats on the shelf 18.

A cavity 23 is disposed at the upper end of the main body 10 between the closure 11 and the vortex finder 19 for receiving a removable filter 24. In use, the filter 24 acts to filter air flowing from the vortex finder 19 to a clean air outlet 25, which leads via a duct (not shown) to a motor/fan unit (not shown).

Referring to FIG. 2 of the drawings, the filter 24 comprises a tubular filter body 26, which contains a filter element 27 of porous material. The filter body 26 is open at its upper and lower ends to allow the passage of air therethrough. A radial formation or series of formations 28 are disposed in a circumferentially and axially confined region on the external surface of the filter body 26.

Referring again to FIG. 1 of the drawings, an arm 29 is pivotally mounted intermediate its opposite ends to the internal surface of the upper end of the main body 10 adjacent the point where the catch 13 engages. A spring (not shown) biases the lower end of the arm 29 inwardly, so that it engages the formation 28 on the filter body 26, the formation 28 preventing further rotation of the arm 29 (in a clockwise direction as shown). In this position, the upper end of the arm 29 is positioned inwardly of the outer wall 17 of the main body 10 and in a position where it does not obstruct operation of the closure 11.

The filter 24 is seated on the flange 22 of the vortex finder 19, the flange 22 having a thickness D. In use, the filter 24 and vortex finder 19 can be removed from the main body 10 for inspection, cleaning or replacement by opening the closure 11.

Referring to FIG. 3 of the drawings, if the vortex finder 19 is omitted during reassembly, it will be appreciated that the filter 24 then seats on the shelf 18 and hence adopts a lower position, which is displaced downwardly from the position of FIG. 1 by the distance D.

In this position, the lower end of the arm 29 no longer engages the formations 28 and hence the lower end of the arm 29 moves radially inwardly under the applied bias. In this position, the upper end of the arm 29 extends over the upper end of the tubular sidewall 17 of the main body 10, thereby obstructing the closure 11 and preventing it from closing fully. In this manner, a user is alerted to the fact that a component of the cleaner is missing or incorrectly installed and that remedial action needs to be taken before the closure 11 can be closed and the cleaner can be used.

Likewise, it will be understood that the arm 29 will adopt the position of FIG. 3 if the filter 24 is missing or if the vortex finder 19 is incorrectly seated. Preferably the formation 28 is disposed on one side only of the filter 24 and preferably at a position where it is closer to one end of the filter 24 than the other. In this manner, the arm 29 will also adopt the position of FIG. 3 if the filter 24 is installed the wrong way around or upside down.

Referring to FIG. 4 of the drawings, there is shown an alternative embodiment of vacuum cleaner which is similar to the vacuum cleaner of FIGS. 1 to 3 and like parts are given like reference numerals. In this embodiment, the cleaner comprises a first separation stage in the form of a single low-efficiency cyclone separator 30. The outlet of the first stage 30 is connected to a second stage 31, in the form of a plurality of parallel-connected mini cyclone separators 32. Each mini cyclone separator 32 comprises a vortex finder 33, which leads to the filter 24. The mini cyclone separators 32 and the vortex finder 33 are provided on respective axially-arranged portions 34,35 of the cleaner, which can be disassembled for cleaning.

When correctly assembled, the filter 24 rests on the second separation stage 31, the latter in turn resting on the first separation stage 30. The filter 24 is thus held correctly in-situ when both stages 30,31 are present and correctly assembled. It will be appreciated that the filter 24 will move out-of-situ if one of the stages 30,31 is omitted or incorrectly inserted. Likewise, the filter 24 will move out-of-situ if a portion 34,35 of the second stage 31 is omitted or incorrectly inserted.

Referring to FIG. 5 of the drawings, in another embodiment the body 10 may be detachable from a chassis portion 50 of an upright vacuum cleaner, so that the body 10 can be removed from the chassis 50 for emptying the separating device therein and for cleaning of the other components within the body 10.

The chassis 50 defines a socket 51 into which the body 10 fits, the socket 51 being dimensioned such that the body 10 can only be reattached when the closure 11 is closed. In this manner, the user will be unable to reattach the body 10 to the chassis 50 following cleaning or emptying if the filter or one of the other separation components of the vacuum cleaner is missing or incorrectly inserted.

A vacuum cleaner in accordance with the present invention is simple in construction, yet is reliably able to alert users to the fact that the filter or one of the other separation components of the vacuum cleaner is missing or incorrectly inserted.

While the preferred embodiments of the invention have been shown and described, it will be understood by those skilled in the art that changes of modifications may be made thereto without departing from the true spirit and scope of the invention. 

1. A vacuum cleaner having a body portion comprising: a cavity; an outlet for cleaned air; a filter removably mounted in the cavity upstream of the outlet; a separation device mounted upstream of the filter for separating and collecting dirt and dust entrained in an induced airflow through the cleaner; a closure for closing an opening in the cavity, the closure being openable for providing access to the filter through said opening; and displaceable means extending into the cavity and arranged to engage the filter for location of the displaceable means in a first position when the filter is correctly in-situ and for location of the displaceable means in a second position when the filter is not correctly in-situ, said displaceable means comprising a portion which obstructs the closure to prevent the closing thereof when the displaceable means is in said second position, wherein said filter is mounted on or against a portion of said separation device, such that said separation device positions said filter correctly in-situ.
 2. A vacuum cleaner as claimed in claim 1, in which a portion of said separation device in said body portion is removable through said opening upon removal of said filter.
 3. A vacuum cleaner as claimed in claim 1, in which said separation device is mounted on or against a portion of a further separation device.
 4. A vacuum cleaner as claimed in claim 1, in which said displaceable means is arranged to engage a formation on said filter, said formation being arranged such that said displaceable means is only held in said first position when said filter is correctly in-situ in said cavity.
 5. A vacuum cleaner as claimed in claim 1, in which said displaceable means is biased into said second position.
 6. A vacuum cleaner as claimed in claim 1, in which said displaceable means comprises an arm having a first end arranged to engage said filter and a second end arranged to obstruct said closure when said filter is not correctly in-situ.
 7. A vacuum cleaner as claimed in claim 6, in which said arm is pivotally mounted intermediate its opposite ends.
 8. A vacuum cleaner as claimed in claim 1, in which said body portion is tubular, said cavity being disposed at one end of the body portion and said closure being provided across an opening in said one end, wherein said separation device is stacked longitudinally inside said body portion between said cavity and an opposite end of said body portion.
 9. A vacuum cleaner as claimed in claim 1, in which said separation device is at least one of a dust bag, a filter and a cyclone separator.
 10. A vacuum cleaner as claimed in claim 9, in which said cyclone separator comprises a plurality of cyclones.
 11. A vacuum cleaner as claimed in claim 1, in which the filter is biased out-of-situ.
 12. A vacuum cleaner as claimed in claim 11, in which the body portion is arranged to be substantially upright when in use, such that said filter is biased out-of-situ by gravity.
 13. A vacuum cleaner as claimed in claim 1, in which said body portion is detachably mounted to a chassis of said cleaner.
 14. A vacuum cleaner as claimed in claim 13, in which said chassis is adapted to prevent attachment of said body portion thereto when said closure is open.
 15. A vacuum cleaner as claimed in claim 14, in which said chassis defines a socket into which said body portion fits when said closure is closed. 